Woven-body floating island

ABSTRACT

A floating island and its method of manufacture, said floating island comprising: warp strands; and weft strands, said weft strands being woven with said warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said strands is a first strand that is comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear or a curvilinear cross section, a second strand that is comprised of a closed-cell polymer foam that contains closed-cell pores, a third strand that is comprised of an open-cell polymer foam that to contains open-cell pores, a fourth strand that is comprised of a bi-cellular polyester foam that contains both closed-cell pores and open-cell pores, a polymer foam strand that is comprised of a closed-cell thermosetting foam comprising a polymer fiber additive, or a polymer foam strand having closed-cell pores and comprising protruding fingers.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119(e) back to U.S. Patent Application No. 60/862,786 filed on Oct. 25, 2006.

BACKGROUND OF THE INVENTION

This invention relates to floating islands. In particular, the invention relates to woven floating islands.

Manmade floating islands have been proven to be useful for numerous environmental applications. Various types of floating islands are currently used for water quality remediation, shoreline protection, waterfowl nesting habitat, and as a renewable food source for fish.

Some currently available floating islands are useful for more than one purpose; for example, some floating islands are designed to simultaneously promote plant growth, support colonization by beneficial microbes, attenuate wave action, and provide wildlife habitat. One example of a floating island product that performs multiple functions is the BIOHAVEN™ Floating Island manufactured by Floating Island International (FII) of Shepherd, Mont. These islands improve water quality by using plants and microbes to remove excess dissolved nutrients such as nitrate and phosphate from the water, while providing a food source (plant roots and bioflim) for fish, and also providing nesting habitat for ducks.

Manmade floating islands have several requirements in order to perform effectively for the applications listed above. First, they must be buoyant, and their buoyancy must be adequate to support additional loads that may occur over time from sources such as plant growth, animal use, and temporary saturation from wave inundation and precipitation. Second, they must have a large effective surface area that is suitable for colonization by beneficial microbes that remove nutrients, since these microbes need an attachment surface in order to thrive. Third, they must be manufactured from durable and nontoxic materials. Also, if plants are to be grown, the islands must be penetrable by plant roots and stems. Finally, the islands should preferably have a natural appearance that is similar in shape and contour to natural islands.

Currently available floating islands that comprise all of the characteristics listed above are manufactured by FII from a combination of nonwoven fiber matrix and buoyant polymer foam. There are no currently available products on the market that use a woven-body construction to perform the functions listed above.

The background art is characterized by U.S. Pat. Nos. 5,224,292; 5,528,856; 5,766,474; 5,980,738; 6,086,755; and 6,555,219 and U.S. Patent Application Nos. 2003/0051398; 2003/0208954; 2005/0183331; the disclosures of which patents and patent applications are incorporated by reference as if fully set forth herein.

BRIEF SUMMARY OF THE INVENTION

The purpose of the invention is to provide a woven floating island. For some applications, it may be desirable to manufacture floating islands using a weaving process. For example, woven floating islands may be more economical to construct than nonwoven configurations for large projects where the surface area required for an island may be several acres in size. In another example, woven islands may be the most economical configuration to manufacture when there is a large quantity of waste material (such as polyethylene or polypropylene) that can be economically melted and extruded into long rolls of polymer foam, which may subsequently be woven into floating islands. In a third example, woven embodiments may be preferable for combining materials with different characteristics into a single island that has the combined characteristics of the various materials—for instance, strands of high-buoyancy, impermeable, closed-cell foam may be woven with strands of permeable, high-internal surface area strands of open-cell foam to produce an island that is both highly buoyant and capable of supporting microbial and macrophyte growth.

The present invention is a floating island manufactured by a weaving process. In preferred embodiments, the invention provides the necessary characteristics of buoyancy, large surface area for microbial colonization, durability, and ability to be penetrable by plant roots and stems. The invention may optionally be manufactured so as to have a natural appearance, by using natural-color materials, and constructing the islands in natural shapes.

The present invention has two more preferred embodiments. In the first embodiment, each of the strands in the weave is specially manufactured so as to have all of the necessary requirements of buoyancy, permeability, and ability to support plant and microbial growth. In the second embodiment, strands with different characteristics are woven together to form a floating island that contains all of the necessary requirements, with each type of strand supplying some of the requirements.

The present invention is well suited to utilize thermoplastic polymer scrap material, which may be recycled as extruded polymer foam strands. These strands may subsequently be utilized efficiently in a woven-body design that is less expensive to manufacture than nonwoven methods, particularly for relatively large islands.

Background art manufacturing techniques for manufacturing extruded polymer foams are well developed, but current manufacturing techniques for manufacturing nonwoven floating islands from polymer foams are not as well developed. Therefore, woven embodiments of floating islands may be more cost effective to produce until nonwoven methods have been more fully developed. diameter) polymer foam strands are likely to be more durable and more cost effective than current nonwoven designs for mitigating against storm damage from very large and high-energy waves.

In a preferred embodiment, the invention is a floating island comprising: a plurality of warp strands, each warp strand having a warp strand diameter; and a plurality of weft strands, each weft strand having a weft strand diameter, said plurality of weft strands being woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is selected from a type consisting of: a plurality of first strands, each of which first strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section, a plurality of second strands, each of which second strands being comprised of a closed-cell polymer foam that contains closed-cell pore spaces, a plurality of third strands, each of which third strands being comprised of an open-cell polymer foam that contains open-cell pore spaces, a plurality of fourth strands, each of which fourth strands being comprised of a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces, a plurality of first extruded polymer foam strands, each of which first extruded polymer foam strands being comprised of a closed-cell thermosetting foam having a polymer fiber additive, and a plurality of second extruded polymer foam strands, each of which second extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers. Preferably, said warp strand diameter differs from and said weft strand diameter. Preferably, said warp strands are a single type and said weft strands are a different single type.

In another preferred embodiment, the invention is a floating island comprising: a plurality of warp strands; and a plurality of weft strand that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section. Preferably, said nonwoven polymer fibers are extruded thermoplastic fibers. Preferably, said extruded thermoplastic fibers are extruded polyethylene fibers, extruded polypropylene fibers extruded polyester fibers.

In yet another preferred embodiment, the invention is a floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a closed-cell polymer foam that contains closed-cell pore spaces. Preferably, said closed-cell polymer foam is a polyethylene foam, a polypropylene foam or a ethylene propylene diene monomer foam.

In another preferred embodiment, the invention is a floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces.

In a further preferred embodiment, the invention is a floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each individual strand comprising a closed-cell thermosetting foam having a polymer fiber additive. Preferably, said polymer fiber additive is a plurality of polyester fibers.

In another preferred embodiment, the invention is a floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands comprises extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers.

In another preferred embodiment, the invention is a composite floating island comprising: a plurality of the single-layer floating islands disclosed herein, stacked vertically one upon the other. Preferably, said warp strand diameter is within the range from about ⅛ inch to about one foot. Preferably, said weft strand diameter is within the range from about ⅛ inch to about one foot.

In yet another preferred embodiment, the invention is 16. A method of manufacturing floating island, said method comprising: selecting a plurality of warp strands; selecting a plurality of weft strands; and weaving said plurality of weft strands with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is selected from a group consisting of: a plurality of first strands, each of which first strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section, a plurality of second strands, each of which second strands being comprised of a closed-cell polymer foam that contains closed-cell pore spaces, a plurality of third strands, each of which third strands being comprised of an open-cell polymer foam that contains open-cell pore spaces, a plurality of fourth strands, each of which fourth strands being comprised of a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces, a plurality of first extruded polymer foam strands, each of which first extruded polymer foam strands being comprised of a closed-cell thermosetting foam having a polymer fiber additive, and a plurality of second extruded polymer foam strands, each of which second extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers. Preferably, the same strand is selected in each of said selecting steps. Preferably, each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section. Preferably, each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a closed-cell polymer foam that contains closed-cell pore spaces. Preferably, each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces. Preferably, each of said pluralities of strands is comprised of a plurality of individual strands, each individual strand comprising a closed-cell thermosetting foam having a polymer fiber additive. Preferably, each of said pluralities of strands comprises extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers.

Further aspects of the invention will become apparent from consideration of the drawings and the ensuing description of preferred embodiments of the invention. A person skilled in the art will realize that other embodiments of the invention are possible and that the details of the invention can be modified in a number of respects, all without departing from the concept. Thus, the following drawings and description are to be regarded as illustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The features of the invention will be better understood by reference to the accompanying drawings which illustrate presently preferred embodiments of the invention. In the drawings:

FIG. 1 is a top plan view of a schematic representation of a preferred embodiment of a woven-body floating island.

FIG. 2 is a side elevation view of the floating island shown in FIG. 1.

FIG. 3 is a schematic cross-sectional view of a preferred embodiment of a first example strand that is comprised of nonwoven polymer fibers that are packed into a round cross section.

FIG. 4 is a schematic cross-sectional view of a preferred embodiment of a second example strand that is comprised of extruded closed-cell polymer foam that contains closed cell pore spaces.

FIG. 5 is a schematic cross-sectional view of a preferred embodiment of a third example strand that is comprised of extruded open-cell polymer foam that contains open-cell pore spaces.

FIG. 6 is a schematic cross-sectional view of a preferred embodiment of a fourth example strand that is comprised of bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces.

FIG. 7 is a schematic cross-sectional view of a preferred embodiment of an alternate stand shape.

FIG. 8 is a schematic cross-sectional view of a preferred embodiment of an extruded polymer foam strand.

FIG. 9 is a schematic cross-sectional view of a preferred embodiment of a fifth example strand with a cross-sectional area that has been designed to have a high surface area for microbial colonization.

The following reference numerals are used to indicate the parts and environment of the invention on the drawings:

-   -   1 floating island     -   2 warp strands     -   3 weft strands     -   4 inter-strand spaces     -   5 first warp strand     -   6 second warp strand     -   7 first weft strand     -   8 second weft strand     -   9 first example strand     -   10 nonwoven polymer fibers, polymer fibers     -   11 second example strand     -   12 closed-cell spore spaces     -   13 third example strand     -   14 open-cell pore spaces     -   15 fourth example strand     -   16 alternate cross-sectional shape     -   17 extruded polymer foam strand     -   18 fifth example strand     -   19 protruding fingers

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a preferred embodiment of woven-body floating island 1 is presented. Shown are the east-west (right-left or “warp”) strands 2, the north-south (up-down or “weft”) strands 3, and the inter-strand spaces 4. Although floating island 1 is shown as having a single layer in FIG. 1, multiple layers may be stacked vertically to produce a thicker composite floating island.

Floating island 1 may be constructed from strands in which the diameter of each strand may range from about ⅛ inch to about one foot, depending on the desired thickness and stiffness of the resulting island, and depending on the characteristics of the material(s) making up the individual strands. For example, closed-cell polyethylene foam strands are currently manufactured in diameters ranging from about ⅛-inch to over one foot. The strands may be of different diameters; for example, the warp strands may have a diameter of 2 inches, while the weft strands have a diameter of 6 inches. Alternately, the warp strands and weft strands may have the same diameter.

Inter-strand spacing 4 may be adjusted during the weaving process depending on the desired characteristics of the finished floating island. For example, relatively large inter-strand spaces 4 may be preferred for islands that are optimized for storm wave mitigation, since inter-strand spaces 4 act to reflect and absorb storm wave energy, thereby decreasing the magnitude of incident wave height and energy. Relatively small inter-strand spaces 4 may be preferable for applications where maximum surface area is desired for colonization of beneficial microbes on and within the strands. For example, a floating island deployed in a marine setting to reduce storm wave intensity may have strand diameters of about one foot and inter-strand spacings of about one foot. A floating island deployed in a lake to reduce dissolved nutrients by microbial and macrophyte uptake may have strand diameters of about ⅛-inch and inter-strand spacings of about 1/32-inch.

With selection of appropriate spacings for the particular application, any of the following can be accomplished: providing optimum root growth medium, providing wave energy dissipation, and containing soil or growth medium while providing permeability for water transport. The spacings may also be non-uniform; for example, some close spacings may be combined with some large spacings to provide soil retention in some areas of an island and wave dissipation in other areas.

Referring to FIG. 2, a side view of floating island 1 of FIG. 1 is presented. Shown are first warp strand 5, second warp strand 6, first weft strand 7, and second weft strand 8. Note that each of the strands 5, 6, 7, 8 may be comprised of either identical or different materials, depending on the design of the particular floating island that is being constructed. For example, floating island 1 may be comprised of different strand materials, wherein each type of strand has some of the required characteristics (e.g., buoyancy or large surface area for microbial growth). By combining different materials into the weave, it is possible to obtain all of the characteristics that the structure requires. By combining materials, floating island 1 may also be optimized for root growth.

FIGS. 3 through 9 present schematic cross-sectional views of different strands having various shapes and materials that are suitable for woven-body island construction. Referring to FIG. 3, first example strand 9 is presented that is comprised of nonwoven polymer fibers 10 that are packed into a round cross section. In a preferred embodiment, fibers 10 are made by extrusion of thermoplastic polymers. The fibers may be made of positively buoyant polymers such as polyethylene or polypropylene. Alternately, fibers 10 may be made of negatively-buoyant polymers such as polyester. Strands that are comprised of nonwoven polymer fibers typically have high permeability to water and gases, a large surface area for colonizing beneficial microbes, and are easily penetrable by plant roots and stems. Americo Manufacturing Company, Inc. of Acworth, Ga., manufactures a polyester-fiber nonwoven material that is similar to the material illustrated in FIG. 3. The background art material is limited in thickness to about two inches maximum.

Referring to FIG. 4, second example strand 11 is presented that is comprised of extruded closed-cell polymer foam that contains closed-cell pore spaces 12. Examples of suitable polymer foam include polyethylene, polypropylene, and ethylene propylene diene monomer (EDPM). Strands that are comprised of closed-cell foam are typically highly buoyant, have low permeability to water and gases, and are resistant to penetration by plant roots and stems. Nomaco of North Carolina manufactures a background art material that is similar to the material illustrated in FIGS. 4 and 5.

Referring to FIG. 5, third example strand 13 is presented that is comprised of extruded open-cell polymer foam that contains open-cell pore spaces 14. The open cells are interconnected, and result in a material that is slightly buoyant, is permeable, has a moderately large surface area for colonizing bacteria, and is penetrable by plant roots and stems.

Referring to FIG. 6, fourth example strand 15 is presented that is comprised of bi-cellular polyester foam that contains both closed-cell pore spaces 12 and open-cell pore spaces 14. Strands that are comprised of bi-cellular foam are moderately buoyant, moderately permeable, have a moderate surface area for colonizing bacteria, and are penetrable by plant roots and stems.

Referring to FIG. 7, an alternate cross-section strand shape 16 is presented. The strand shown in FIG. 7 is square in cross section, but other shapes such as rectangular, triangular or elliptical may also be used. In the case of strands made from nonwoven polymer fibers 10, the strands may be cut from larger sheets of manufactured material. In the case of polymer foam material (not shown), the strands may be extruded.

Referring to FIG. 8, extruded polymer foam strand 17 is presented that is comprised of closed-cell thermosetting foam with one or more polymer fiber additives. In this embodiment, extruded polymer foam strand 17 is produced by adding polymer fibers 10 such as polyester fibers to the thermosetting polymer resin prior to melting and extrusion. Fibers 10 absorb and wick water, while closed-cell pore spaces 12 provide buoyancy. Strands that are comprised of extruded polymer foam with fiber additives are moderately buoyant, moderately permeable, have a moderate surface area for colonizing bacteria, and are penetrable by plant roots and stems.

Referring to FIG. 9, fifth example strand 18 is presented with a cross-sectional area that has been designed to have a high surface area for microbial colonization. In this embodiment, strand 18 is made from extruded polymer foam with closed-cell pore spaces 12 and protruding fingers 19. The strand is highly buoyant. Microbes can colonize the external surfaces of the strand, and plant roots and stems can grow between the protruding fingers 13 of adjacent strands.

In a first more preferred embodiment of the present invention, each of the weft and warp strands are identical, and each of the strands is manufactured so as to have the characteristics of buoyancy, permeability, and suitability for supporting microbial and macrophyte growth. The strands illustrated in FIGS. 8 and 9 are preferred for constructing the first more preferred embodiment.

In a second more preferred embodiment, different types of strands are woven together to form a floating island that, in composite, has the characteristics of buoyancy, permeability, and suitability for supporting microbial and macrophyte growth.

Many variations of the invention will occur to those skilled in the art. Some variations include weaving together identical types of strands to produce a floating island. Other variations call for weaving together different types of strands to produce a floating island. All such variations are intended to be within the scope and spirit of the invention.

Although some embodiments are shown to include certain features, the applicant(s) specifically contemplate that any feature disclosed herein may be used together or in combination with any other feature on any embodiment of the invention. It is also contemplated that any feature may be specifically excluded from any embodiment of the invention. 

1. A floating island comprising: a plurality of warp strands, each warp strand having a warp strand diameter; and a plurality of weft strands, each weft strand having a weft strand diameter, said plurality of weft strands being woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is selected from a group consisting of: a plurality of first strands, each of which first strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section, a plurality of second strands, each of which second strands being comprised of a closed-cell polymer foam that contains closed-cell pore spaces, a plurality of third strands, each of which third strands being comprised of an open-cell polymer foam that contains open-cell pore spaces, a plurality of fourth strands, each of which fourth strands being comprised of a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces, a plurality of first extruded polymer foam strands, each of which first extruded polymer foam strands being comprised of a closed-cell thermosetting foam having a polymer fiber additive, and a plurality of second extruded polymer foam strands, each of which second extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers.
 2. The floating island of claim 1 wherein said warp strand diameter differs from and said weft strand diameter.
 3. The floating island of claim 1 wherein said warp strands is a single type and said weft strands are a different single type.
 4. A floating island comprising: a plurality of warp strands; and a plurality of weft strand that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section.
 5. The floating island of claim 4 wherein said nonwoven polymer fibers are extruded thermoplastic fibers.
 6. The floating island of claim 5 wherein said extruded thermoplastic fibers are extruded polyethylene fibers, extruded polypropylene fibers extruded polyester fibers.
 7. A floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a closed-cell polymer foam that contains closed-cell pore spaces.
 8. The floating island of claim 7 wherein said closed-cell polymer foam is a polyethylene foam, a polypropylene foam or a ethylene propylene diene monomer foam.
 9. A floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces.
 10. A floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is comprised of a plurality of individual strands, each individual strand comprising a closed-cell thermosetting foam having a polymer fiber additive.
 11. The floating island of claim 10 wherein said polymer fiber additive is a plurality of polyester fibers.
 12. A floating island comprising: a plurality of warp strands; and a plurality of weft strands that are woven with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands comprises extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers.
 13. A composite floating island comprising: a plurality of the floating islands of claim 1, stacked vertically one upon the other.
 14. The floating island of claim 1 wherein said warp strand diameter is within the range from about ⅛ inch to about one foot.
 15. The floating island of claim 1 wherein said weft strand diameter is within the range from about ⅛ inch to about one foot.
 16. A method of manufacturing floating island, said method comprising: selecting a plurality of warp strands; selecting a plurality of weft strands; and weaving said plurality of weft strands with said plurality of warp strands to produce a single-layer woven body having inter-strand spaces; wherein each of said pluralities of strands is selected from a group consisting of: a plurality of first strands, each of which first strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section, a plurality of second strands, each of which second strands being comprised of a closed-cell polymer foam that contains closed-cell pore spaces, a plurality of third strands, each of which third strands being comprised of an open-cell polymer foam that contains open-cell pore spaces, a plurality of fourth strands, each of which fourth strands being comprised of a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces, a plurality of first extruded polymer foam strands, each of which first extruded polymer foam strands being comprised of a closed-cell thermosetting foam having a polymer fiber additive, and a plurality of second extruded polymer foam strands, each of which second extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers.
 17. The method of claim 16 wherein the same strand is selected in each of said selecting steps.
 18. The method of claim 16 wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands being comprised of a plurality of nonwoven polymer fibers that are packed into a rectilinear cross section or a curvilinear cross section.
 19. The method claim 16 wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a closed-cell polymer foam that contains closed-cell pore spaces.
 20. The method of claim 16 wherein each of said pluralities of strands is comprised of a plurality of individual strands, each of which individual strands comprising a bi-cellular polyester foam that contains both closed-cell pore spaces and open-cell pore spaces.
 21. The method of claim 16 wherein each of said pluralities of strands is comprised of a plurality of individual strands, each individual strand comprising a closed-cell thermosetting foam having a polymer fiber additive.
 22. The method of claim 16 wherein each of said pluralities of strands comprises extruded polymer foam strands having closed-cell pore spaces and comprising protruding fingers. 